The Siam Army Air Corps were formed in 27 March 1914 and became Kongtap Agard Thai (Royal Thai Air Force, or RTAF) on 24 June 1939. according to [c2e98] it adopted a roundel based on the national flag in 1917 with "national" rudder stripes. Those marking (except making the rudder marking smaller) are the same as today after their re-adoption in 1945. See pre-WWII, Current

[c2e98] reports that after war broke out between Thailand and France in 1941, in order not to be mistaken by the roundels, the RTAF replaced the roundel with the national flag.

In Dec. 1941, Thailand was taken over by Japan and became a puppet state. It adopted (according to [c2e98]) the Siam 1855-1916 flag and also adopted a marking made of Japanease roundel on one wing and the flag ot the other wing and tail. In 1945 the former marking were re-adopted.Dov Gutterman, 26 Jun 2003

The image in the Flaggenbuch is incorrect (the biggest mistake in this otherwise monumental book, IMHO) in that it omitted the crown and that the badge's background was not a disc. The Singha Beer image is much closer to the real thing.Miles Li, 6 Sep 2005

The Airforce Flag (B.E.2505) [1962 AD]
This tricolor flag is similar in design to the national "Trairanga". In the top left-hand corner – the one next to the flagpole – stands the Royal Crown together with an ordinal number – in yellow – depicting the King's place within the dynasty as a whole. Beneath this are the Royal initials in red, trimmed in yellow. As a final touch, blue shards light radiate from top of the crown itself. In the middle stands a blue circle with the Air Force's coat of arms in the center. Along the inner edge – i.e. the one next to the flagpole – runs a red-and-black cord. The other three borders are trimmed in yellow braid, 2 cm. wide. [Similar to the Air Force Flag 1936-1962, above, but with a circular emblem and with crown and initials.]

Also known as the "Chaichalermpol flag", the Air Force flag first made its appearance in B.E.2479 [1936 AD], with one minor change, namely the addition of the Royal emblem in the top left-hand corner next to the flagpole itself. The flag shown here was first used in B.E.2505 [1962 AD]. Nowadays, there is a new design which was created following a special Royal Decree, issued in B.E.2522 [1979 AD], concerning flags.

Santiago Dotor, 29 Oct 1999

The Royal Cipher should occupy the upper white stripe only, surrounded by
either yellow sunbursts or blue Thai writings (neither is shown on this GIF),
and the Royal Crown above it should occupy the upper red stripe only, with no
rays. Yellow fringe, red sleeve, and plain streamers in the colours of the
National Flag bow-tied onto a black flagpole with a golden Royal Crown finial.Miles Li, 7 May 2009